Spath - if I and Mr J2 (85 on Sat.) found ourselves in this situation with a young, armed man threateningly on our premises late at night, we would think first of our own lives. By entering someone else's property, armed and with evil intent, you put yourself at risk, presumably you accept the risk that you may be killed. It is most certainly not sociopathic to defend yourself and if, during that process, the intruder's weapon is turned on him then so be it.
I'm a very peaceable person, but I would defend myself and my husband to the death in this situation - him or us. Anyway, as the aop says, this is the usual dance.